//part1:C02:ex2.22.cpp
#include <iostream>

int main(void)
{
    int i = 0;
    int *p1 = nullptr;
    int *p = &i;
    if (p1)
        std::cout << "p1 pass" << std::endl;
    if (p)
        std::cout << "p pass " << std::endl;
    if (*p)
        std::cout << "i pass" << std::endl;    
    return 0;
}